A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Sandra, a 29-year-old orangutan at Buenos Aires' zoo, on May 20, 2015. Sandra got cleared to leave a Buenos Aires zoo that was her home for 20 years, after a court ruled she was entitled to more desirable living conditions. (Photo by Juan Mabromata/AFP Photo)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

In this handout photo provided by Warner Brothers Pictures and Village Roadshow Pictures, Tom Cruise plays Lieutenant Colonel Bill Cage, a soldier who replays his last day while trying to fight aliens, in director Doug Liman's “All You Need Is Kill”. The film is set to premiere on March 14, 2014. (Photo by David James/Warner Brothers Pictures)

“Teenager Teenager”, an installation by the collaborative Chinese artists Sun Yuan and Peng Yu, at the exhibition “Crazy. Madness in contemporary art” in Rome on February 18, 2022. (Photo by Gloria Imbrogno/LiveMedia/Rex Features/Shutterstock)

Lucha libre is Mexico’s version of what in the United States refer to as pro wrestling. Its dates to 1863, when a Mexican wrestler named Enrique Ugartechea developed a form of “freestyle” wrestling that was based on Greco-Roman wrestling. Lucha libre began to soar in popularity in Mexico after two Italian businessmen started promoting fights in the early 1900s. It has since become popular around the globe. Here: Juliza meets with colleagues at her home. (Photo by Diana Bagnoli/The Washington Post)

A six-year-old acrobat performs on the opening of a tourist festival in Bozhou, Anhui province, China May 3, 2015. (Photo by Reuters/China Daily)

Photographer Brian Finke spent nearly two years traversing the friendly skies, following the life of flight attendants in the air and on the ground, from Delta and Hawaiian Air, to Hooters Air, Southwest, Air France, British Airways, Air Asia, and dozens more. His images of flight attendants waving, applying makeup and deboarding plans while smiling appear as if they were ripped from an advertisement in a glossy magazine. Here: Tiger Airways, Singapore, 2006. (Photo by Brian Finke/The Washington Post)